After a politically messy few weeks that forced them to play defense, Democratic leaders will return to work next week hoping to shift attention back on their top priorities — namely, a universal health care package and a climate change overhaul.

Congress enters a two-month legislative sprint starting June 1. But a slew of intraparty squabbles and ongoing controversies over torture and terror threaten to bog down the meat of the Democrats’ summer agenda.

Speaker Nancy Pelosi (D-Calif.) has made it clear that she will no longer discuss her explosive charge that the CIA lied to her about the use of waterboarding in 2002.

“What we are doing is staying on our course and not being distracted from it in this distractive mode,— the Speaker said at a press conference last week long on rhetoric and short on questions. “We are going forward in a bipartisan way for jobs, health care, energy, for our country.—

Pelosi instead exulted in the passage of landmark climate change legislation by the House Energy and Commerce Committee after an epic markup. But that bill — like the health care overhaul — faces a messy road ahead.

Agriculture Chairman Collin Peterson (D-Minn.) said last week that he has more than 40 Democratic votes to kill the measure unless significant changes are made to benefit rural areas, and Ways and Means Chairman Charlie Rangel (D-N.Y.) said he planned to put the bill on the back burner until he finished marking up a health care overhaul.

And significantly, four conservative Blue Dog Democrats — Reps. Mike Ross (Ark.), John Barrow (Ga.)., Charlie Melancon (La.), and Jim Matheson (Utah) — voted against the bill in committee, which could portend trouble for it on the House floor and in the Senate. Ross and other Blue Dogs had complained loudly that Waxman and other key Democrats did not bring them in early enough in the drafting of the health care or cap-and-trade bills.

Some on the left, meanwhile, are unhappy with the compromises and concessions to industry groups that Waxman made to secure the votes of other moderates for the package, with some environmental groups trying to kill it in favor of Environmental Protection Agency regulations over carbon emissions.

The Senate, meanwhile, started moving ahead on renewable electricity standards, although it is well behind the House on climate change legislation. And both chambers have much work to do on the writing of a health care bill, with key areas of contention being a public insurance option and tax increases.

But House Majority Leader Steny Hoyer (D-Md.) sought to minimize the discord.

“My observation and experience of the last couple months is both on health care and on energy, we are working with all the members of the caucus, and I’m pretty confident we’re going to create consensus on these issues,— Hoyer said in a recent interview.

Hoyer noted that the party has weathered similar divisions before.

“In 2007, we had somewhat of the same sort of an argument — a wringing-the-hands argument — is there going to be a big blowup in reference to [fuel economy] standards and there wasn’t. We reached agreement and consensus, passed a bill, sent it to the president, the president signed it, and for the first time in 30 years modified the [mileage] standards.—

He predicted Peterson and Rangel would ultimately climb on board. “Just as we had nine committees on the [2007] energy bill, we were able to create a consensus, and I believe we’ll be able to create a consensus here,— he said.

Hoyer also said he and Pelosi and the rest of the leadership are in sync.

“You have seen over the last two and a half years a very unified party, and I think that remains,— he said.

Indeed, Hoyer spent much of last week as a personal flak jacket for Pelosi on the torture flap, given that she refused to answer any more questions on the issue.

Hoyer said the larger issue of the treatment of detainees could be looked at by a bipartisan, 9/11-style commission as well as the Intelligence committees.

An outside panel could “look at this not from a gotcha or finger-pointing standpoint,— but instead to examine “what happened, how did this happen and how do we go forward.—

Democrats also have a full plate of other agenda items to wrap up, including finishing the war supplemental and turning to fiscal 2010 spending bills and a major transportation bill, and approving a slew of Senate nominations. And they have to resolve the dispute over President Barack Obama’s plan to close the Guantánamo Bay, Cuba, prison, and what to do with any displaced detainees.